1. Field of the Invention
The present invention relates generally to magnetic memory devices including magnetic random access memory (MRAM) elements for data storage and particularly to magnetic memory devices used to emulate static random access memories (SRAMs).
2. Description of the Prior Art
Static random access memory (SRAM) has been used prevalently throughout the recent decades for storage of binary information or data in applications such as computers, handheld devices among many other electronics applications. SRAMs have fast read and write access times making them excellent candidates for applications in need of such requirements. For example, as central processing units (CPUs) have acquired increased speeds, faster memory has been required to keep up with them—SRAMs fit this bill. Similarly, as electronic devices have decreased in size, so have size requirements of SRAMs.
However, due to manufacturing constraints, limitations of manufacturing SRAMs in terms of size and speed have been anticipated and are now being experienced. Thus, devices replacing SRAMs are highly sought-after devices. One such candidate is magnetic random access memory (MRAM). MRAMs have the advantage of being smaller in size, and being non-volatile where data or information stored therein is retained even after power is disconnected. Also, MRAM's read access time is comparable to that of SRAMs. But when it comes to writing/programming/storing of data, MRAM suffers from slower than that of SRAM. It is well known that the write access time of an MRAM is generally longer than its read access time. Thus, while MRAMs hold their own against SRAMs in terms of read access times, they cannot do the same in terms of write access times.
In an effort to compensate for MRAMs' longer write access time, current memory designs employ “burst” operations by increasing the number of data units written to memory. “Burst” refers to writing a number of data units during a write access operation or before the completion of a write operation. However, burst operations require data units to be sequential and because not all data or even most data is sequential, and additionally large bust sizes are not practical.
Thus, the need arises for a non-volatile memory device such as MRAM with comparable system performance to SRAM.